Rear feels bouncy

Ever since I put my lift with the All-pro standard 3" leafs w/ Icon RR +2 shocks (TW member used shock) the rear of my truck seems like it is bouncing up and down slightly like the tires haven't been balanced. The truck seems to drive much better with a few hundred lbs in the back too. I have a brand new set of SCS wheels and new tires that were just balanced. I also had another set of wheels and tires on my truck and it did the exact same thing.

I have no extra weight in the bed of my truck for the leafs. It does this mainly around 55mph lower speeds it doesn't do it as much and high speeds on the freeway above 65 it doesn't either.

Could this be something wrong with the shocks, something not tight, or not installed properly?

Any input would be greatly appreciated.

 

nobody has had this issue?

 

With stiffer springs it's always possible to hit some harmonic on certain road surfaces at certain speeds. Check your leaf pack U-bolts are tight and the upper shock mounts are tight. If no problems found, you can send the shocks in to be rebuilt for more damping.

You are certain what you are feeling is suspension bounce and not driveline vibration (another thing that can appear with rear lifts)?

 

Cool I will check all bolts when I get home and upper shock mounts. Nah doesn't feel like the driveline vibration. Maybe I will take out one of the CB washers I used for spacers and see if that does anything. Currently I have 3 on each bolt.

 

Could it be the shocks themselves being that they are Icons and I only drive on the freeway 90% of the time?

 

I put in Deavers, took them about 200 miles to settle down. They started out feeling very jumpy but they're much smoother now. But I wouldn't say that felt like unbalanced tires, just bouncy only when going over bumps. +1 for double checking all of your bolts, especially the leaf packs. They compress over time and you may need to tighten them. I went for 80 ft/lb- Toyota manual says 30 or something ridiculous which is way too low.

 

I had a set of allpro standard with ICON RR VS serie and change it for a custom set of deaver at 3 in of lift. They were too stiff for me. I prefer them smooth and progressive and add a set of timbren bumpstop to compensate for load.